Thank you for your reply. I checked the given file link. But it does not fulfil my purpose. I want to capture the events such as new booking , booking approved, booking denied, booking pending, booking deleted. For your reference, I am sharing below file links and line number where updation is required. Please look into these files and revert back to me as soon as possible.

Hello.
Its will be available in next update 8.7.6
Currently you can simply add that function into the php file (../booking/core/wpbc-dev-api.php).
I can not say about the exact date of update release. Sorry.
Kind Regards.

2. We have smsalert plugin so we require phone field in booking form. we do not want users to add the phone field manually.You have already done it for email field i.e is automated created by plugin and non-removable. Please suggest a solution for it.

2) Unfortunately, we can not set the “phone” field as required field for the booking form. Some customers, sometimes need even Email field to set as not required, so setting phone field as required will make confusing for many customers.
Thank you for understanding.